Brandone breaks cages better than Ramtut, and that is certainly a reason to get Ramtut. So cage breaking is legit. Some might not want to try, but it's legit. A reason to take MA+?!?... probably not, though.

But back to MA+ and it's merits... granted Gabe is a special case, but the MA+ helps recover when he is down from the Diving Tackle. It also helps him gets places he normally would have to GFI. MA+ is always an option for someone you need to move. And you don't have to move them much, but Tombers need to move.

That being said - MA+ is not as important as other standard skills. Given the choice, I think I would much rather have a Tomber with Stand Firm, Guard and Mighty Blow than one with MA+ and two of those three. But MA+ later in the progression is definitely worth considering.